Remove 'String::append' from some of the blink source.

Source/core/fetch/CSSStyleSheetResource.cpp

Index: Source/core/fetch/CSSStyleSheetResource.cpp
diff --git a/Source/core/fetch/CSSStyleSheetResource.cpp b/Source/core/fetch/CSSStyleSheetResource.cpp
old mode 100644
new mode 100755
index 7952ec5da2ec71af331f574e7073183978add410..06e42be5e1ed03fd7338027a52e578ce0812b164
--- a/Source/core/fetch/CSSStyleSheetResource.cpp
+++ b/Source/core/fetch/CSSStyleSheetResource.cpp
@@ -88,8 +88,7 @@ const String CSSStyleSheetResource::sheetText(bool enforceMIMEType, bool* hasVal
         return m_decodedSheetText;
 
     // Don't cache the decoded text, regenerating is cheap and it can use quite a bit of memory
-    String sheetText = m_decoder->decode(m_data->data(), m_data->size());
-    sheetText.append(m_decoder->flush());
+    String sheetText = m_decoder->decode(m_data->data(), m_data->size()) + m_decoder->flush();

[abarth-chromium, 2014/01/07 16:10:33]

This change is wrong because the order of evaluation for + isn't defined by C++.

     return sheetText;
 }